This invention relates to the general field of value-, credit- and access control cards which incorporate one or more large scale integrated circuits for receiving processing and memorizing information from a terminal, as well as imparting similar information to such a terminal and to display data in humanly readable form either on the terminal or on the card or on both.
Cards containing memory chips can hold not merely data about credit accounts, but also the equivalent of money, that is spendable small cash amounts for instant use. The user of the "card" mauy decide from which account or money compartment respectively any particular payment is to be made. The personal identification number, according to one of my inventions, can be keyed into the "card" directly. For all practical purposes, the "card" becomes a purse, with the added advantage that in an event of accidental loss or theft, no other person can spend anything from the stored credit accounts, or the stored money register of the card.
Present trends aim at making the card of dimensions identical to a traditional credit card. Terminals being designed to read and write such cards reliably by first drawing the card mechanically into a protected read/write area and subsequently conveying the card back to the point where it was offered to the machine. This system is satisfactory where but a few high-value transactions are required to be carried out where the time factor is unimportant. However, one could enumerate a large number of medium-to-small cash vending transactions which are required to take not much time, perhaps one second at the very most. Cards are usually carried inside a wallet or plastic purse from which a given card has first to be extracted before it can altogether be offered to the vending mechanism. If the latter is fairly slow in operation, it is clear that the total time for a transaction may be between 10 to 20 seconds, by the time the card has been safely replaced into the wallet or purse. It is somewhat incongruous that a card combining electronically addressable value sections and having the same, if not greater, versatility and security than a conventional wallet, is at present still designed to be put into a wallet. One is reminded of the early combustion vehicles which makes everywhere built in close imitation of a horse-drawn carriage. One reason why most people still prefer the often very cumbersome method of paying in coins and bills is that it is still faster than the present day method of paying by credit or money card. A need thus exists for making the electronic purse ergonomically self-contained, that is to say to design its form and the manner of interfacing it with a reader device as to render the "card" conducive to everyday usage within the limits dictated by reliability and desirability.